Practical Chemistry activities accompany and. Catalysis, Chemical reaction, Chemistry 1725 Words 8 Pages Lab Report: Halogen Reactions Purpose: This experiment will allow for exploration into some of the properties of Group 17 elements halogens and their compounds. Elements and compounds can move from one phase to another phase. Charlie Wilson Written by: Dipen Patel I. The result is that a simple relation exists between the Sherwood number describing the mass transfer process and the Nusselt number describing the heat transfer process. Squeeze out water as much as possible.
It is of great importance to recognize and identify the different instruments and laboratory tools, because in this way will we be able to use them properly and also to call them by name and know why. This paper presents experimental and simulation studies on spherical samples of naphthalene sublimation in the presence of air as driving agent. It is possible to use other materials that sublime including iodine, naphthalene and dry ice carbon dioxide. What else produces it besides respiration? You can also choose from plain, jacquard, and dobby. Reaction between starch and Iodine produce a dark grey, black color and it means that the test is positive. During sublimation, the filter flask was rotated in the sand bath, to ensure all the green solid was sublimated.
. This is because psychologists and more. Sometimes, however, it can be impractical to use dry ice. The total volume of aqueous extract was about 10 to 12 mL. With the blower operating, the timer was started at the same time the shutoff valve was opened. Procedure: In a 50 mL beaker place 15 mL of water, 2.
Salinity was also measured at each site, but there was no salt present because all sites consisted of fresh water. Hold the tube in the neck of the conical flask so that its base is suspended about a third of the way down into the body of the flask. Criminalistics: Forensic Science, Crime and Terrorism. Iodine that crystallises can be reused, but any remaining deposits can be cleaned by soaking the equipment in a bath of 1 M sodium thiosulfate. Head loss in piping system. Additionally, the filter flask was not allowed to completely cool prior to being weighed, so the mass of the flask may have been different than when cool.
By studying genetics and inheritance, plants and animals have progressed biologically which means they are more productive and in cases, have more nutrients. To avoid any contact with the naphthalene surface during the measurement phase, a pair of tweezers was used to transport the module while contacting only the module pins. The water soluble materials in the tea leaves are extracted into hot water. The pure product collects on the cold finger and be scraped off, leaving non-volatile impurities at the bottom of the apparatus. Since the process requires additional energy, it is an change. There will be a 1-inch or 25. After Run Measurements In order to obtain the overall or local mass transferred only overall mass transfer is described here , the measurements performed before the run step 4 are repeated after the data run.
In this photo below, we can see blades of ice with hollows where the ice has sublimated. With two sets of apparatus side by side, you can quickly demonstrate the effect of rapid growth of crystals on their size. You'll find many cool science fair projects and educational science toys that will amaze and entertain you. As dry ice is heated, it crosses this point along the bold horizontal line from the solid phase directly into the gaseous phase. Lesson organisation This experiment is best done as demonstration. The one that proved most successful is shown in Figure 2. Regaining solid iodine from iodine vapor can be achieved by cooling down iodine vapor on a cold surface.
Conclusion In this experiment crude caffeine was extracted from tea leaves, and had a mass weight of 0. The process is employed as a means of purification of certain substances, which are heated in closed pans or retorts. Table of Reagents Discussion The extraction yield refers to the percent of caffeine in the tea leaves at start of the extraction experiment. With the naphthalene test module placed in the test section, the desired flow rate over the card was set during the prerun period. Summary The mass transfer technique has been described to obtain the convective heat transfer from the surfaces of electronic modules mounted to a printed circuit card. The sodium carbonate was placed into the solution to keep the caffeine from becoming slightly acidic protonated , which would prevent the caffeine from being able to be separated once the organic solvent dichloromethane was added to the solution, as a charged species dissolves in the aqueous layer while a neutral species goes to the organic layer.
After extracted caffeine was dried, green solid was noted on the bottom of the filter flask, also known as the crude caffeine. Candy, Candy bar, Candy bars 603 Words 3 Pages lab reports becca Medina Biology Lab 1107 Lab Notebook The Scientific Method Problem: Will a male or female have a higher heart rate after participating in the physical activity of running up three floors of a building? The relative electronegativities of the halogens will be determined. Applying the root sum square of the individual uncertainties of each variable measured gave results that were estimated to be within 3%. After the tea bag cools enough to handle, squeeze out water as much as possible, being careful not to break tea bag. To determine the dissolved oxygen content, the LaMotte Kit or Winkler Method was used.